(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

f(t)=e^(t+7)

2. Relevant equations

£{f(t)}=∫e^(-st)f(t)dt

3. The attempt at a solution

so i insert my f(t) into the formula, came up with ∫e^(-st+t+7)dt

using u substitution, u=t(-s+1)+7, du=(-s+1)dt so it follows that 1/(-s+1)∫e^(u)du=e^(u)/(-s+1)

so I plug u back in, and should be able to find my answer from there, only I come up with an answer very different from the one in the book, which is e^(7)/(s-1)

Can anyone help me out?

So i figured it out, I set u=-1(t(-s+1)+7)=t(s-1)-7, and put e^-u inside the integral. turns out just making myself look at it a little longer worked out

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# Homework Help: Laplace transform issue

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